QUALITY TEST AND PLANNING OF SLUDGE TREATMENT INSTALLATION OF WATER TREATMENT PDAM

Tujuan pada penilitian ini, untuk mengetahui kualitas dan perencanaan pengolahan lumpur instalasi pengolahan air PDAM. Metode yang digunakan mengenai tahapan pengampilan sampel yaitu dengan grab sampling, dan pengambilan dilakukan selama 8 hari. Pengambilan sampel lumpur dilkakukan pada pipa yang didiamkan mengalir selama 30 detik agar didapatkan debit konstan. Analisa untuk uji kualitas lumpur IPA PDAM dilakukan di laboratorium. Hasil dari penelitian mengenai uji kualitas pada pipa pembuangan lumpur pada unit sedimentasi. Data yang dibutuhkan meliputi data primer, dan sekunder. Hasil dari penelitian ini mengenai uji kualitas lumpur dari instalasi pengolahan air PDAM, memiliki nilai rata-rata pH 7,7, suhu 27°C, kekeruhan >1000 NTU hal ini dikarenakan kualitas air baku yang memiliki kandungana koloid tinggi. Total solid memiliki nilai rata-rata 281.772 mg/L, total suspended solid dengan nilai rata-rata 52.134 mg/L, COD memiliki nilai rata-rata 3.100 mg/L, dan BOD 3,96 mg/L dengan nilai ratarata . Debit rata-rata harian lumpur yang dihasilkan dari instalasi pengolahan air sebesar 145,773 m3/hari. Unit yang direncanakan sesuai dengan kualitas, dan volume yang diketahui maka direncanakan unit pengolahan lumpur meliputi bak pengumpul, gravity thickening, belt filter press, dan bak pengumpul dry cake. Anggaran biaya yang direncanakan untuk perencanaan pengolahan lumpur instalasi pengolahan air sesuai dengan unit yang diperlukan membutuhkan anggaran dana sebesar Rp. 1.037.900.00,00.

Effect of Ultrasonic Frequency on Thickener Performance

Gravity thickening is an important aspect to solve numerous environmental and safety problems that were created by tailings discharging at low solid concentrations. Furthermore, in order to efficiently facilitate the separation of released water and solid sediments, a continuous thickening system with ultrasonic equipment has been used to investigate the thickening performance of copper-mine tailings under different ultrasonic frequencies (16 kHz, 20 kHz, 22 kHz, 25 kHz, and 28 kHz). After freeze-drying treatment, the underflow samples are imaged using the scanning electron microscope (SEM); then, the structure of floc or aggregates in the SEM images is quantifiably analyzed using the software of Image J. Results show that the underflow concentration increases as the ultrasonic frequency increases and decreases afterwards. A linear logarithmic function can explain the relationship between underflow concentration and run time at a certain ultrasonic. The underflow concentration is maximized at 64.47 wt. % when the ultrasonic frequency is 22 kHz. Based on the analysis on the microstructure of underflow samples, the minimum pore average size and pore average fraction are obtained when the ultrasonic frequency is 22 kHz, implying that 22 kHz is the optimum ultrasonic frequency combining the results of the underflow concentration.

Experimental investigation of Microcystis aeruginosa cyanobacteria thickening to obtain a biomass for the energy production

The purpose of the presented research is to analyse possible methods of thickening of the Microcystis aeruginosa (Kützing) Kützing cyanobacteria using the obtained concentrate as a biomass for the production of energy carriers and biologically valuable substances. Method of cyanobacteria thickening under the action of electric current and in the electric field, as well as the method of coagulation–flocculation and gravity thickening, was experimentally investigated in labscale conditions. Electrical methods didn't show positive results for the Microcystis aeruginosa thickening, despite the reports of their potential efficiency in a number of previous studies. The high efficiency of the method of coagulation– flocculation and gravity thickening of Microcystis aeruginosa suspensions was obtained. The optimum concentrations of industrial polymeric coagulants and flocculants for the thickening of Microcystis aeruginosa suspensions were defined in the range of about 10 ppm for the coagulants and about 1 ppm for the flocculants. Negative effect of the previous cavitational treatment of the diluted suspensions of Microcystis aeruginosa on the effectiveness of the coagulation–flocculation and gravitational thickening was confirmed experimentally. Hydrodynamic cavitation should be recommended to use after the thickening as the next step of processing of concentrated suspensions of Microcystis aeruginosa to achieve maximum extraction of energy carriers and biologically valuable substances.